"Over the last couple of weeks, Mozilla has finally stepped up its 64-bit testing process. There are now five slaves dedicated to building Firefox for Windows x64, which means that from Firefox 8 and onwards, you'll be able to pick up 64-bit builds that are functionally identical to its 32-bit cousins but operating in native 64-bit CPU and memory space." Th 64bit version is about 10% faster, benchmarks show.

I was disappointed that AMD developed AMD64, not because it wasn't an improvement. It is, but because it means the complex x86 ISA will remain the top desktop CPU for another decade or two at the expense of better alternatives.

If you don't like X86-64, there is always: SPARC, POWER7, MIPS64. Get one of these so you can conceptualize cleanly in 64-bit brain space :-)